Plaster edge strips



March 7, 1967 R. E. TATUM PLASTER EDGE STRIPS Filed July 13, 1964 All/ uuufluuununu INVENTOR.

ROY E. TATUM GLQQW QQMWW ATFQRNEY$ Patented Mar. 7, 1967 3,307,313 PLASTER EDGE STRIPS Roy E. Tatum, Detroit, Mich., assignor to Blakely Prod- This invention relates to edge strips for edging the borders of plaster-like coatings-applied upon wall surfaces.

In applying relatively thick, finish coatings of plaster or plaster-like material to wall surfaces, it is extremely difficult and time consuming to form straight, sharp corners and edges as well as to maintain a uniform coating thickness. This is particularly true where the coatings are formed of such plaster-like materials as small pieces or chips of stone mixed with plastic resins or with plaster.

Thus, it is an object of this invention to provide edge strips which form straight corners, upper and lower edges and joints, during application of relatively thick coatings of plaster-like materials upon wall surfaces, and which strips also function to guide the thickness of such coatings. These and other objects and advantages of this invention will become apparent upon reading the following description, of which the attached drawings form a part.

In these drawings:

FIG. 1 is an elevational view of a portion of a wall surface, prior to coating, but with various edge strips arranged thereon.

FIG. 2 is an enlarged, cross-sectional view of a corner strip taken in the direction of arrows 2-2 of FIG. 1.

FIG. 3 is an enlarged, cross-sectional view of a bottom edge strip taken in the direction of arrows 33 of FIG. 1.

FIG. 4 is an enlarged, cross-sectional view of an upper edge strip taken in the direction of arrows 4-4 of FIG. 1, and

FIG. 5 is an enlarged, cross-sectional view of a pair of joint strips taken in the direction of arrows 5-5 of FIG. 1.

FIG. 6 is an enlarged cross-sectional view of a modified corner strip.

FIGS. 1 and 2 illustrate a wall surface 10 formed upon a wall 11, which may be made of rough plaster, masonary, etc, and having a corner 12. A relatively thick, finish coating 13, is applied upon the Wall surface 10. FIG. 1 omits the coating 13 for illustration purposes.

The coating which may be approximately A to inch in thickness, may be formed of conventional finish plaster or of one of the many available plaster-like finishing materials, such as a mixture of small chips or pieces of stone and a suitable plastic resin or plaster.

The wall surface 10 is prepared for the coating by having mounted thereon a corner strip 14 fitted over the corner 12, a base strip 15, an upper edge strip 16 and joint strips 17 separated by conventional caulking 18 for forming expansion joints. The strips are each of uniform cross-section and may be roll-formed or formed of metal or plastic extrusions. The coating is applied after the strips are arranged upon the wall surface.

The corner strip 14 (see FIG. 2) is formed of two, integral legs or strip portions 20 each having a wall surface contacting inner face 2|1 and an outer face 22, with the inner faces 21 arranged at a right angle. The outer faces 22 converge toward the inner faces so that the legs 20 are tapered into wedge-like shapes. The strip also includes an outwardly extending, integral, guide flange 23 having a narrow outer edge 24 and tapered opposite edges or faces.

The legs 20 are each provided with a number of spaced apart openings 25.

Upon an existing Wall 11 there is applied at certain locations an initial coating of cement or plaster. Before this dries the strips are applied thereto. Some of the cement or plaster enters holes 25, thereby joining the strip to the wall 11. The finished coat of plaster is then applied to the wall up to and over the strips 14, 15, 16, 17 or 40 to provide straight edges and sharp corners.

The base strip 15 (see FIG. 3) includes a leg 20, identical to that previously described, and a flange 26 whose upper edge 27 is formed at an acute angle relative to the leg outer surface 22, to thereby from a continuous, horizontal notch or groove, which is filled by the lower edge of the coating 13.

The upper edge strip 16 (see FIG. 4) has an upwardly extending flange 28, formed on its leg 20, with a face '29 arranged at an abtuse angle relative to the leg outer face 22.

The joint strips 17 (see FIG. 5) may be used in pairs. Each has a leg 20 and an integral flange 30 whose outer edge 31 is arranged perpendicular to and whose inner edge 32 is arranged at an obtuse angle relative to the inner face 21 of its leg. The space between the flange inner edges 31 may be filled with conventional caulking 18 to thus provide an expansion joint.

Each of the flanges 23, 26, and 30 extend outwardly, from the inner faces 21 of their respective legs, the same distance to thereby jointly provide a guide for determining the thickness of the coating 13. Hence, by arranging his plastering darby across the flanges of two spaced apart strips, a plasterer, by moving his darby in contact with such flanges, will simultaneously smooth out the coating and make it evenly thick.

While the above strips are each indicated as being in a specific location, they may be used interchangeably at times, such as by using the upper strip as a base strip, etc.

FIG. 6 illustrates a modified corner strip 40 whose flange 41 is formed in a generally T-shape. The opposite ends 42 of the head of the T are arranged substantially parallel to the legs 20 to form grooves 43 which receive the coating material. The head of the flange is exposed, that is, not covered by the coating, as compared with flange 23 of FIG. 2 which is substantially concealed by the coating.

This invention may be further developed within the scope of the following claims. Accordingly it is desired that the fore-going description be read as being merely illustrative of an operative embodiment of this invention and not in a strictly limited sense.

I now claim:

An extruded aluminum edge strip for edging the border of a relatively thick coating of plaster-like material applied upon a wall surface, comprising a long, uniform solid cross-section, thin, narrow, strip portion having a flat, wall surface contacting, inner face and an opposite, outer, flat face arranged in a plane converging towards said inner face so that the strip portion is tapered in crosssection with one wide edge and an opposite narrow edge;

a continuous, narrow, flange portion integrally joined with said strip portion at said wide edge, said flange having an outer face intersecting said strip portion outer face at an obtuse angle and an inner face intersecting the wide edge of said strip, said strip portion inner face and said flange inner face forming an obtuse angle, said outer and inner faces of said flange converging from said wide edge to an outer edge spaced from the plane of the strip portion in- 3 ner face extended and parallel to said strip portion 1,449,745 3/ 1923 Clapp 52--255 Wide edge; 2,196,086 4/ 1.940 Sprouse et al. 52255 wherein said strip portion may be applied to a wall sur- 2,796,641 6/ 1957 Wollaeger 52-255 face and thereafter covered by said plaster-like mate- 3 201,90 19 5 Arnold 52 255 rial, with the flange thereby edging said material and 5 gaging the thickness of the coating. FOREIGN PATENTS 237,627 2/ 1962 Australia. References Cited by the Examiner 1 291 91 3 19 2 France UNITED STATES PATENTS 1, 03 7/ 196 2 Germany- 290,750 12/1883 Da Cunha 52-255 10 1,318,330 10/1919 Mann X FRANK L. ABBOTT, Primary Examiner.

1,420,040 6/ 1922 Jones 52255 A. C. P'ERHAM, Assistant Examiner. 

